I can't speak for the Pacific Northwest, but in Nassau County, Long Island, all fuel, including HHO, in now ULS fuel. It should be a plus for retailers and homeowners, as it will not produce the ash that the 500 and 5000PPM fuels did.
AFAIK, the original 5000PPM fuel has not been available for some time. There is still some 500 PPM fuel in the system for use in ships and locomotives. That will probably be gone by 2015 when new emission standards for locomotives take effect.